1. Field of the Invention
The present invention relates generally to riding mowers and, more particularly, to an improved deck suspension system for mowers or the like. Known art can be found in U.S. Class 56, subclass 320 and in other classes and subclasses.
2. Description of the Known Art
Those skilled in the art will appreciate that riding mowers have been a staple for maintaining residential yards, commercial lawns, golf courses and highway rights of way for many years. They are seen moving along grass in many settings including grassy center dividers and along the sides of roads in rough, sometimes rocky terrain, and in all sorts of attitudes from flat and level to severe side hills.
In many instances, as an operator mows a particular area rough or rocky ground is often encountered and riding mower decks have been traditionally suspended beneath the mower to “float over” to permit movement of the mowing deck relative to the vehicle so that the vehicle can move past such obstructions. Many of these known devices use chains or cables or another similar suspension tactics that primarily rely upon the weight of the deck to suspend and orient it beneath the mower. A problem often encountered when mowing is that the deck is deflected when an obstruction is struck and then the deck fails to properly return to its normal mowing orientation and/or height relative to the mower. Another problem is that the deck is deflected too much and leaves a large area unmowed, which area then requires additional attention.
For example, our previous U.S. Pat. No. 6,854,252 used a chain system to suspend the mowing deck. While this system is generally satisfactory, it could be improved with a system that suspended the deck more definitively.
Known art which may be relevant to the present invention includes the following patents with their abstracts, the teachings of which are incorporated by reference.
U.S. Pat. No. 6,105,349 issued on Aug. 22, 2000, to Busboom, et al., titled Riding lawn mower having a liquid-cooled engine shows a lawn mower including a liquid-cooled engine having a radiator grille positioned over the radiator thereof. The radiator grille includes a perforated screen member having a series of alternating grooves and ridges formed therein which run downwardly and rearwardly from the forward end of the screen member. The design of the screen member and the radiator grille permit the perforated screen member to self-clean and also provides a convenient means by which the screen member may be manually cleaned, if necessary. This mower uses a chain suspension system for its mowing deck.
U.S. Pat. No. 6,062,333 issued on May 16, 2000, to Gordon titled Riding mower with pivoting front wheel assembly shows a riding mower or other like four-wheel vehicle has the two front wheels mounted off the cantilever end of a subframe which is pivotably attached to the underside of the main frame of the vehicle by two spaced part pivots lying along the vehicle length axis. A cutter deck is suspended from the main frame beneath the subframe. The subframe construction resists bending forces, due to front-to-back and vertical forces on the dropped-down front wheels, when they encounter obstacles or depressions. The main frame is made of steel tubing, and provides a generally rectangular space just forward of the driver's seat, suitable for placement of the driver's feet. Preferably, the subframe also has a generally rectangular opening, nominally aligned with the main frame opening, to also accommodate the driver's feet. The elevation of the driver's seat can thus be desirably lowered, to maintain a low center of gravity. This mower uses a chain suspension system for its mowing deck.
U.S. Pat. No. 5,280,695 issued on Jan. 25, 1994, to Nunes, Jr., et al. titled Wide area lawnmower shows a wide area mower which can be attached to and detached from a tractor in a relatively short time. In one disclosed embodiment, the mower has a main frame which is detachably connected to the rear mount of a tractor, swing frames pivotally connected to the main frame for movement into and out of engagement with the side mounts of the tractor, means detachably locking the swing frames in engagement with the side mounts, and mowing heads mounted on the frames to the sides and rear of the tractor. In another disclosed embodiment, the mower includes a frame adapted for connection to a towing vehicle, a pair of side decks positioned on opposite sides of the frame, a center deck positioned between the side decks, a pair of rear decks positioned to the rear of and between the side decks and the center deck. Ground engaging wheels at the front and rear of each deck support the decks, with the wheels at the rear of the side decks and the center deck being aligned with the wheels at the front of the rear decks, and means pivotally mounting the decks to the frame so that the decks can follow the contour of the ground. This device relies upon the small wheels on the mower decks to support the mower decks, which are undesirable since they place the weight of the deck on the ground and do not transfer the mowing deck weight to the larger wheels of the mower itself.
Also, commercially available equipment and components may be relevant, including hollow metal frames, shoe brushes and the like. Such equipment may be used in implementing an exemplary embodiment in accordance with the present invention.
None of these references, either singly or in combination, disclose or suggest the present invention. It is desirable to have a improved lawnmower to address the perceived shortcomings of the known art.
While it is evident from past attempts that suspension systems for lawnmowers are desirable, the known art is limited in its teaching and utilization, and an improved system is needed to overcome these limitations. An improved suspension system should provide a simple and efficient system for meeting the various needs of the users and the like.